Methods of drying yarns and apparatus therefor

ABSTRACT

A process for the drying of yarn on packages in a kier in which air is drawn through the kier by a vacuum pump to lower the boiling point of the water in the packages in order to &#39;&#39;&#39;&#39;flash off&#39;&#39;&#39;&#39; the moisture to promote quicker and more efficient drying of the packages and apparatus for carrying out the process.

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[54] MEETHQIUfi U11 UTMYHNG if/111K013 AND [56] likeiferences Cilted APP MATUs T ERIE UM UNITED STATES PATENTS [72] $333 gff iiig fgggzfi 690,592 1/1902 Lapp ..34/15 3,528,180 9/1970 Karrer et a1. ...34/15 X [73] Assignee: William Taittmi 8: C0. 11.111111111112111, Leek, En- 2,567,940 9/ 1951 Karrer et ..34/l7 gland 3,259,995 7/1966 Powischill 34/50 [22] Filed: 1%9 Primary Examiner-Frederick L. Ma'tteson [21] A 1,N Wmfim Assistam Examiner-Ronald C. Capossela Attorney-Norris & Bateman [30] Foreign Appfimfiom Priority 13 mm 57] AHQHRACT Aug. 16, 1968 Great Britain ..39,l95/68 A pmcess for the drying f yam on packages in a in which I air is drawn through the kier by a vacuum pump to lower the [52] US. (:1 34/15, 34/1 7, 34/29 boiling point of the water in the packages i Order to fl h [51] 11111112. 11:! .JFZMB 5/041 the moisture to promote quicker d more efficiem [58] lFnefld 011 Search ..34/26, 92, l5, 17, 104 FD, ing f h packages d aratus for carrying out the process.

3 Cllaims, 3 Drawing; Figures l/VVEN7U? STEWART JACKSON & ARTHUR HARRISON MFA/w) a 6 PATEMEUFEBzR 1am nvl/E O'? STEWART JACKSON R ARTHUR HARRISON mmmm SHEET W 3 min /Nl/N7'OE STEWART JACKSON & ARTHUR HARRISON (P am won/WU METHODS Oil DlltlrihlG vanus ANU AlPllAllitA'lllUS 'lllilllEltlElFUEt This invention relates to an improved process for drying yarn on packages and apparatus therefor.

According to the invention the process comprises drawing air into a drying kier by a vacuum pump which extracts air therefrom, reducing the air intake to the kier when a predetermined temperature has been attained therein and continuing to gradually reduce the air intake while maintaining the inlet and outlet temperatures equal, reducing the pressure or vacuum in the kier to lower the boiling temperature of any water therein, and maintaining this pressure until the outlet and inlet air temperatures remain constant for a predetermined time.

The invention will be described with reference to the accompanying drawings:

FIG. l is an elevation of the yarn dryer showing one machine operating one kier;

FIG. 2 is a plan of same;

FIG. 3 is a diagrammatic elevation showing a bank of kiers.

A yam-drying kier A of known construction is provided with a suction pipe 1 connected to a vacuum pump 2 and a second pipe 3 open to atmosphere at d and having a heater battery 5 between the inlet of the second pipe 3 and the known kier A.

In operation the drying process is carried out in two stages.

The yarn packages B on a frame or frames b are inserted into the kier in known manner. Air is drawn into the kier with the lid or cover a open, the air being at ambient temperature is more dense, and therefore the water which has been absorbed by the packages B is removed by the force of air drawn through rather than by air absorbing moisture.

The second stage comprises closing lid or cover a of the kier and subjecting the packages B to heated air drawn through the second pipe 3 and over the heating battery 5. A probe 6 is provided in the pipe t, a second probe 7 in the pipe 3 and a third probe ii in the kier A. When the temperature of the outlet air from the kier is equal to the inlet temperature a valve 9 is gradually closed to restrict the air inlet and a predetermined negative pressure or vacuum is created in the kier so that the moisture left in the packages is flashed oft" or vaporized so that in this gaseous form the vapor is removed by the vacuum purnpZ giving uniformity of drying to all packages.

The negative pressure in the kier is controlled according to the yarn being dried.

For example for a yarn to be dried at 200 F. a vacuum of 6% inches of Hg will cause the moisture to vaporize or boil and be drawn out of the kier with the heated air. The yarn is dry when the outlet and inlet temperatures as registered by the probes h, 7 in the kier remain constant.

Thus when the outlet or discharge temperature coincides with the inlet temperature the kier is subjected to a vacuum, this allows the boiling point of water to be reduced to the discharge temperature (i.e., the higher the temperature the lower the vacuum, the lower the temperature the higher the vacuum) so that any remaining moisture will flash off and in this vaporized form is removed by the vacuum pump 2.

The vacuum pump 2 is driven by a motor ill and the exhaust from the pump may be passed through a separator 12 to extract the moisture therefrom, the air from the separator 12 being exhausted through a silencer 21.

In operation the water extracted by the pump 2 when the lid or cover a of the kier is open is contaminated by soap or other impurities and a valve 13 is opened to allow the water to pass to a drain. When the lid or cover a has been closed the water withdrawn may be passed to a reservoir by changing over the valve 113 to close the outlet to the drain.

The pipes l and 3 may be provided respectively with a further valve lit, 19.

Further pipes 114i, 115 may be provided connecting the pipe 1 to the pipe 3 each provided respectively with a valve lb, 117 so that by closing the valves lit l9 and opening the valves l6, 17 the direction of flow of the air through the kier A may be reversed.

A bank of klers A may be provided operated by a plurality of pumps as shown in W6. 3 the pumps and separators being arranged below a floor C or in a room C to reduce noise on the kier room.

What we claim is:

l. A process for drying yarn on packages in a kier having a cover and provided with inlet and outlet openings in two stages comprising a first stage during which air at ambient temperature is drawn through the kier with the cover open by a vacuum pump to extract water from the packages; and a second stage, after closing the cover, during which heated air is drawn by suction throughthe inlet opening and the interior of said kier and withdrawn through said outlet opening and the pressure within the kier is subsequently further lowered after the outlet air temperature becomes substantially equal to the inlet air temperature to reduce the vaporization temperature of moisture remaining in the yarn and efliectively flash off said remaining moisture which is removed by vacuum, continuing the passage of heated air through the kier until the inlet temperature and the outlet temperature are again substantially equal and maintaining flow of heated air through the kier for a predetermined time thereafter under the same condition.

2. in a process for drying yarn in packages disposed within an enclosure having an inlet and an outlet, the steps of applying suction for passing heated air into said inlet and through said enclosure over the yarn to be withdrawn at said outlet, further reducing the pressure within said enclosure by restric tion of the air supply when the outlet air temperature becomes substantially equal to the air temperature at said inlet to reduce the vaporization temperature of moisture remaining in said yarn and effectively flash off said remaining moisture which is removed by vacuum, and continuing passage of heated air through said enclosure for a predetermined time under conditions of reduced pressure within the container and substantially equal inlet and outlet air temperature.

3. Apparatus for drying yarn comprising a kier within which packages of yarn are adapted to be mounted, said kier having an inlet and an outlet, suction means, conduit means connect ing said suction means to said outlet, means for supplying heated air at said inlet so that said heated air may be drawn over said yarn by said suction means, temperature probes at said inlet and outlet, means for restricting flow of said heated air into the kier to reduce the pressure therein when the air temperatures at said inlet and outlet are substantially equal and valved interconnections between said supply of heated air and said conduit means for reversing connection thereof to said inlet and outlet for reversing the: direction of flow of heated air through said kier. 

1. A process for drying yarn on packages in a kier having a cover and provided with inlet and outlet openings in two stages comprising a first stage during which air at ambient temperature is drawn through the kier with the cover open by a vacuum pump to extract water from the packages; and a second stage, after closing the cover, during which heated air is drawn by suction through the inlet opening and the interior of said kier and withdrawn through said outlet opening and the pressure within the kier is subsequently further lowered after the outlet air temperature becomes substantially equal to the inlet air temperature to reduce the vaporization temperature of moisture remaining in the yarn and effectively flash off said remaining moisture which is removed by vacuum, continuing the passage of heated air through the kier until the inlet temperature and the outlet temperature are again substantially equal and maintaining flow of heated air through the kier for a predetermined time thereafter under the same condition.
 2. In a process for drying yarn in packages disposed within an enclosure having an inlet and an outlet, the steps of applying suction for passing heated air into said inlet and through said enclosure over the yarn to be withdrawn at said outlet, further reducing the pressure within said enclosure by restriction of the air supply when the outlet air temperature becomes substantially equal to the air temperature at said inlet to reduce the vaporization temperature of moisture remaining in said yarn and effectively flash off said remaining moisture which is removed by vacuum, and continuing passage of heated air through said enclosure for a predetermined time under conditions of reduced pressure within the container and substantially equal inlet and outlet air temperature.
 3. Apparatus for drying yarn comprising a kier within which packages of yarn are adapted to be mounted, said kier having an inlet and an outlet, suction means, conduit means connecting said suction means to said outlet, means for supplying heated air at said inlet so that said heated air may be drawn over said yarn by said suction means, temperature probes at said inlet and outlet, means for restricting flow of said heated air into the kier to reduce the pressure therein when the air temperatures at said inlet and outlet are substantially equal and valved interconnections between said supply of heated air and said conduit means for reversing connection thereof to said inlet and outlet for reversing the direction of flow of heated air through said kier. 